Clothes drying apparatus



April '16, 1963 M. A. BARBEE CLOTHES DRYING APPARATUS Filed Dec. 5, 1960frzveri f- Marion G.ficzr-5ee United States 3,085,349 CLOTHES DRYINGAPPARATUS Marion A. Barbee, Eflingham, Ill., assignor to Borg- WarnerCorporation, Chicago, Ill., a corporation of Illinois Filed Dec. 5,1960, Ser. No. 73,884 3 Claims. (Cl. 3489) Where a lint trap or otherfiltering device is used to filter the drying air as it leaves theclothes dryer, it is a common occurrence for the lint trap or filter tobecome clogged with lint to the extent that it greatly restricts theflow of drying air. This situation usually occurs, without the knowledgeof the operator, with the result that the dryer fails to properly drythe clothes. In severe cases, a substantial blocking of the drying airwill occur which will result in extremely poor efiiciency or possiblyeven failure of the dryer. It is therefore extremely important toprovide a clothes drying apparatus whereby the operator will be alertedwhen there is a substantial restraint of flow of the drying airresulting from clogging of the lint trap.

An important object of the invention is to provide a signalling devicefor a clothes drying apparatus of simple and economical construction forindicating a malfunction of the dryer.

More particularly, it is an object of this invention to provide asignalling device for a laundry drying apparatus, wherein air iscirculated to dry the laundry, which will provide an audible warning tothe operator of an obstruction in the path of the circulating air.

With these and other objects in view, the present invention contemplatesa laundry drying apparatus having a blower for providing, a stream ofair through the apparatus to dry the laundry. The air is exhaustedthrough a lint trap or lint collector which is designed to remove lintfrom the'air stream. An audible signal device, such as a whistle, isexposed to the air stream so that part of the stream will passtherethrough. In the eventthe lint trap "becomes clogged with lint, thepressure will build up within the dryer and thus increase the volume ofair passing through the device, with the result that the device willproduce a signal sound when a predetermined pressure is reached Withinthe dryer and thus indicate to the operator that the lint trap isclogged and re quires cleaning.

Other objects, advantages and novel aspects of the invention will becomeapparent upon consideration of the following detailed description, inconjunction with the accompanying drawings, wherein:

FIG. 1 is a vertical sectional side view of a laundry drying machineshowing alternate positions of the signalling device in or adacent thepath of the air stream.

FIG. 2 is a view of one embodiment of the signalling device taken fromwithin the laundry machine showing a lint screen and bafiie as a partthereof.

FIG. 3 is a sectional View taken along line 3-3 of FIG. 2 showing thewhistle of the signalling device positioned between a protector and ascreen and baffie.

FIG. 4 is a sectional view through a second embodiment of the signallingdevice showing the whistle thereof mounted in a crest which in turn issecured in a bezel within the enclosing panel of the drying apparatus.

Referring to FIG. 1 there is illustrated a clothes dryer with which thepresent signalling device may be associated. The presently discloseddryer structure, except for the signalling device, is fully disclosed inReiter Patent No. 2,798,306. The dryer is generally designated by theice numeral 10 and comprises a frame 11 and a laundry basket 12. Thelaundry basket is rotatably mounted within the frame 11 by virtue of ashaft 13 secured to the basket 12 and pivotally mounted within the frame11, and a pair of spaced rollers 14 in rolling engagement with an outersurface -15 of the basket. The rollers 14 are secured to parallel shafts16 which arerotatably supported in the frame 11. A pulley 17 is rigidlysecured to one of the shafts 16 and motor (not shown) is adapted torotate the pulley 17 to rotate the basket on the rollers 14. A door 18is provided in the frame 11 to provide access to the basket 12.

A blower 20 is provided for directing air through the machine, asindicated by the arrows (FIG. 1), and includes a series of fan blades 21mounted on a hub 22 which is rotatably mounted on a shaft (not shown)within the shaft 13. A pulley 23 is rigidly secured to the hub 22 and isalso driven by the motor (not shown), which drives the rollers 14. Itshould be noted that the air enters the machine at 24, passes through aseries of heating coils 25, is drawn into the blower 20 and subsequentlyexhausted into the basket 12 where it absorbs moisture from the clothes.The moisture-ladened air in the basket 12 is then exhausted from thebasket through openings 26 and enters an exhaust manifold 27 where itleaves the machine through an opening 28.

A lint trap 30 is provided in the exhaust manifold 27 for the purpose ofremoving lint and other foreign matter from the exhaust air as it passesthrough the exhaust manifold 27. The lint trap 30 requires periodiccleaning to free it from lint and other matter which it collects duringoperation of the machine, so that the machine can have a free flow ofair for highest drying efficiency.

The signalling device of the present invention is generally designatedby the numeral 35 (FIGS. 1-4), and will produce sound audible to theoperator, when the lint trap 30 is substantially clogged. Thus, theoperator will be signalledwhen the lint trap needs cleaning. Thesignalling device 35 can bepositioned either at 35a (FIG. 1) in the door18 of the machine, at 35b in the frame 11, at 35c in the basket, or at35d adjacent the basket 12 in the frame 11. It should be noted that inall of these alternative positions, it is a prerequisite that thedevice'be exposed to the path of the air as it passes through themachine. More particularly, the signalling device 35 has one sideexposed directly to the path of the air flowing through the machine andthe opposite side open to the atmosphere so that, should the lint filterbecome clogged, the air will build up pressure in the dryer so that itwill be by-passed from the normal path thereof to the atmosphere throughthe signalling device 35.

One embodiment of the signalling device 35 is illustrated in FIGS. 2 and3 and includes a whistle 36 having two concentric opposed concavo-convexdiscs 37 and 38. These discs have respective openings 39 and 40 in thecenter thereof to allow air to pass through as indicated by the arrows(FIGS. 3 and 4). The shape of the whistle 36 is such that, upon apredetermined rate of flow of air through the openings, a whistlingsound will be produced.

The whistle 36 of the signalling device 35 (FIGS. 2 and 3) is protectedon the outside by a shield 41 which has an opening 42 to allow the freeflow of air therethrough from the signalling device 35. The device 35 isprotected on the inside of the dryer by a baflle 43. The whistle 36 andthe shield 41 are retained in a sleeve 44 which is held in the wall ofthe machine at one of the alternatively selectable positions 3-5a-35d. Alint screen 45 is provided between the whistle 36 and the baflle 43 soas to prevent lint clogging of the whistle.

Another embodiment of applicants invention is illustrated in FIG. 4 andincludes the whistle 36 as illustrated in FIGS. 2 and 3. In thisembodiment, the whistle 36 8 is mounted in a shield 50. The shield 50has an air opening 51 and is frictionally supported in the frame orother of the alternative positions (36a36d) by a sleeve or bezel 52.

In operation, the blower 20 and the basket 12 are actuated by the motorso that the blower causes air to be circulated as indicated by thearrows (FIG. 1) when the basket 12 is rotated. After the air enters themachine at 24, it is pre-heated by the heating elements 25. The blowerforces the hot air through the basket 12 so that it will absorb moisturefrom the laundry and have a drying effect thereon. The moisture-ladenedhot air then passes through the openings 26 in the basket 12 andsubsequently through the lint trap 30 in the exhaust manifold 27 and theexhaust opening 28.

During the operation of the machine, the lint trap 30 will collect lintand other foreign matter from the air to prevent these materials frombeing exhausted from the machine. Eventually, the lint trap will becomeclogged with lint, if it is not periodically removed and cleaned. Underthese circumstances, the flow of air will be greatly retarded orcompletely stopped by the clogged lint trap. Inasmuch as the blower 20will nevertheless continue to operate, a high air pressure will becreated between the blower 20 and the lint trap 30 with the result thata greater volume of air will be forced through the signalling device 35.When the lint trap 30 is sufficiently clogged, to a predetermined state,the volume of air forced through the whistle 36 will be sufiicient tomake the whistle operative so that it will produce an audible sound tosignal the operator of the clogged condition of the lint trap.

It is to be understood that my invention is not to be limited to thespecific constructions and arrangements shown and described, except onlyinsofar as the claims may be so limited, as it will be understood tothose skilled in the art that changes may be made without departing fromthe principles of the invention.

I claim:

1. A signalling device for a laundry drying machine comprising thecombination of a blower for providing a stream of pressurized airthrough the drying machine, a lint filter in the exhaust path of saidair stream, a sound producing signalling device exposed to said airstream and adapted to allow part of 'said pressurized air to venttherethrough to the atmosphere, said signalling device having a whistlein the path of said vented air and operable thereby when said airpressure is higher than a pre- 4 determined maximum, due to lintclogging said filter, a filter screen secured to said signalling devicefor filtering air prior to venting through said whistle, a bafllesecured to said signalling device adjacent said filter screen forprotecting said screen, and a shield secured to said signalling deviceadjacent the atmospheric side of said whistle.

2. A signalling device for a laundry drying machine comprising thecombination of a blower for providing a stream of pressurized airthrough the drying machine, a lint filter in the exhaust path of saidair stream, and a sound producing signalling device exposed to said airstream and adapted to allow part of said pressurized air to venttherethrough to the atmosphere, said signalling device having a whistlein the path of said vented air and operable thereby when said airpressure is higher than a predetermined maximum due to lint cloggingsaid filter, a filter screen secured to said signalling device forfiltering air prior to venting through said whistle, a battle secured tosaid signalling device adjacent said filter screen for protecting saidscreen, and a vented shield between said whistle and the atmosphere andhaving an opening in alignment with the opening in said whistle.

3. A signalling device for a laundry drying machine comprising thecombination of a blower for providing a stream of pressurized airthrough the drying machine, a lint filter in the exhaust path of saidair stream, a sound producing signalling device exposed to said airstream and adapted to allow part of said pressurized air to venttherethrough to the atmosphere, said signalling device having a whistlein the path of said vented air and operable thereby when said airpressure is higher than a predetermined maximum due to lint cloggingsaid filter, a 'filter screen secured to said signalling device forfiltering air prior to venting through said whistle, a bafile secured tosaid signaling device adjacent said filter screen for protecting saidscreen, a vented shield between said whistle and the atmosphere havingan opening in alignment with the opening in said whistle, and a bezelfor mounting and frictionally retaining said signalling device in thedrying machine.

References Cited in the file of this patent UNITED STATES PATENTS2,698,000 Rainsbury Dec. 28, 1954 2,753,831 Davies July 10, 19562,779,305 Dunkelman Jan. 29, 1957

1. A SIGNALLING DEVICE FOR A LAUNDRY DRYING MACHINE COMPRISING THECOMBINATION OF A BLOWER FOR PROVIDING A STREAM OF PRESSURIZED AIRTHROUGH THE DRYING MACHINE, A LINT FILTER IN THE EXHAUST PATH OF SAIDAIR STREAM, A SOUND PRODUCING SIGNALLING DEVICE EXPOSED TO SAID AIRSTREAM AND ADAPTED TO ALLOW PART OF SAID PRESSURIZED AIR TO VENTTHERETHROUGH TO THE ATMOSPHERE, SAID SIGNALLING DEVICE HAVING A WHISTLEIN THE PATH OF SAID VENTED AIR AND OPERABLE THEREBY WHEN SAID AIRPRESSURE IS HIGHTER THAN A PREDETERMINED MAXIMUM, DUE TO LINT CLOGGINGSAID FILTER, A FILTER SCREEN SECURED TO SAID SIGNALLING DEVICE FORFILTERING AIR PRIOR TO VENTING THROUGH SAID WHISTLE, A BAFFLE SECURED TOSAID SIGNALLING DEVICE ADJACENT SAID FILTER SCREEN FOR PROTECTING SAIDSCREEN, AND A SHIELD SECURED TO SAID SIGNALLING DEVICE ADJACENT THEATMOSPHERIC SIDE OF SAID WHISTLE.